Carburetor



C. H. KlRBY June. 10, 1930.

CARBURETOR 5 sheets-sheet i v Filed June Y. 1926 WEE CARBURETOR A 's sheets-sheet 2 C. H. KIRBY Filed June 7, 1926 June `l0, 1930.

June 10, 1930. c. H. KIRBY 1,763,361

' CARBURETOR` Filed June 7. 192e r s sheets-sheet 5 2 Charie; J5. Kirby Paiemea June io, ieso @HABILES IHS. KIRBY, QELINT, MICHIGAN, ASSIGNOR TO MARVEL UARBURETER COMPANY, Gli."'Filflflllh4 MICHIGAN, A COPORTION OF ILLINOIS' CARBURETOR 'application nieu .rune r, ma serial no. 114,104.

rlhis invention relates to carburetors for carburetor partlybroken away to show one internal combustion engines. form of the device of this invention.

lt is an object ofthis invention to provide Figure 2 is a fragmentary section showing a carburetor suitable for the demands of rapid a slightly modified form of accelerating pump 't andsusta'ined acceleration when used in convalve.

nectioiu'withv automotive vehicles and the like, .Figure 3 is a fragmentary section showing and to obtain this object, a pumping type. a modified form of accelerating fu'el resercarburetor is' provided with an auxiliary voir. i chamber adapted to receive themajor part Figure 4 is a fragmentary section showing of this pump discharge 'and to feedl this extra .another modified form of reservoir. i 60 fuelto the nozzle after the completion of Figure is a fragmentary section showing the pump stroke to giveaprolonged acceleratan adjustably controlled bypass for reducing charge.l I have found that' an extra ing the accelerating charge. charge of fuel pumpedthrough the nozzle Figure 6 shows another form of fuel resery 15. givesexellent results for short acceleration Voir. l e5 periods,but if the acceleration demand is Figure 7 is a variation of Figure 1, showprolonged much beyond the pumping period ing independent channel between pump chamthat 4the engine will hesitate' or falter because ber and reservoir. of thehlag in normal fuel pick up and de- As shown on the drawings:

livery through the manifold. It is ,to be A portion of a carburetor bodyis ndi- 70v understood thatthe carburetor nozzles sup-y cated bythe nunieralflO in each figure, .the ply suflicient fuel for thefull power of the mixing chamber 11, the choke valve l2, the engine, but thel difficulty, lies in getting enough high s peed nozzle 18, and the low speed nozzle fuel into the cylinders during a 'sudden pick 14, with adjusting needle 15, being also in'- '25 up, the bestmethod being to supply an extra dicated in certain gures. A flap valve 16, 75 amount of fuel by pumping, which fuel will servesv to restrict the air inlet to the mixing be carried to the'cylinders by the inrushiiig chamber proper and in association with the air faster than the normalincrease-in nozzle nozzle 13 functions as a variable orifice vendelivery, because a large partof the normal turi.l This high speed nozzle 13 discharges 3 0 fuel supply reaches the cylinders by slowly 'through a slot 17in the flap 16, when the flap so l traveling as a liquid onv the wallsof the mani 1s in approximately closed position for the l fold. y slow speed range, as this nozzle, while nor- Itis also an object of thisinvention to pro- Inally the high speed nozzle, also serves as an vide an improved form of accelerating pump acceleralilzing nozzle in :certain of the embodi l' e i ur lus of fuel into tem orar men S S 0WI1` i gtl'lggl 1g esfep back after the 'pm'g Coni- T he end ofthe throttle shaft is indicated at pltes its Stroke i 18 i'n Figure 1. The throttle lever 19 is Y It is another obj-ect of this invention to pion double-endedand of the form of a bell-crank,

l Y one end 20 carrying an adjustable stop screw 40 .vldefan mlfoedl form 'fdaceierm Illpzzle' 21 contactingthe abutment 22 formed on the A9o fed rom t e fue S-tore urn-1g e e wary carburetor body.v The extra arm 23 of the stroke of the acceleratingpump. b i h Other and further objects of this invention 251;? l lpugsn hee tsltll Il degli v will be apparent from tl'avdisclos'ures'in'the accelerating pump is Operated by means of Specification and accompanying drawings' the plunger24,`^linked to the arm 2O of the o5` The invention in a Pl'fel'l'ed form is illus' throttlelever b a bar 25 pivoted at 26 to the tratedin the drawings and hereinafter more arm 20 t fully described. l The pump referred to comprises a cylinder On thedrawings: ,27 formed in a boss on the side of the float Figure 1 is afragmentary elevation 'of a bowl, the lower end'of the cylinder having an 100 i enlarged chamber 28, separated from the pump cylinder proper by a plug 29.having a metering orifice '3 0 therein. A piston 31 is -area ofthe orifice when pered oi toa small diameterlfor the central v part of its length to enlarge the effective downwardly.

The above description holds good for all the modifications shown wltli the exception of that of Figure 2, wherein a metering pinV 34, independent of the piston isprovided with x a .ball35 and is urged upwardly by a spring 36, to seal the central-orifice except when the pin ispressed down by the the bottom of its stroke.

`supply to the high speed nozzle is maintained `by a by-pass 37, in the side of the orificel plug. .The same by-p'ass 37, for constant indepen ent ow, is shown 1n Figure 1, the metering pin making a close it inthe orifice 30, in this the abruptness of movement vides a simple means Y Figure 1 stroke .atthe same time aj et from the high speed nozzle and after the view. The passage 38, is of than a ball check 41. The

ballis formed as a gradual case to serve as a closure when the pin is in its upperposition.

In al1 the modifications the same form of velocity responsive .check valve is used, a horizontal passage y38, being provided in communication with the pump cylinder above the orifice plug. This passage is fed from the float bowl 39,'by the passage40, shown in end larger diameter seat 42, for this taper up which the ball must be lifted bythe velocitjT of the fuel, and th'e angle `of this seatdetermines Y of the accelerating pump necessary to close this check valve and'so cause the accelerating pump to eject fuel into the carburetor proper.- This proerating pump inactive during gradual opening movements ofthe throttle when an extra supply of fuel is not required.

The form of aum'liary reservoir shown in for maintaining the accelerating fuel supply after-thc end of the pump Astroke comprises a ball check valve 43, and cage 4 4, openinglfrom the fuel passage 45, supplying the hig `speed nozzle',.together with an enclosing reservoir 46. Y reservoir is through the port'` 47, in the lower art of a tube 48, which is open tothe incomm air at 49, and leads down into the reservoir and then up. in the form of a nozzle 50, to

the right of the iapvalve.v VThe air inlet 49, serves to mix air with the fuel flo to the nozzle 50, thus assisting in atomizing t e fuel. i With this arrangementthe reservoirtends to ll up during 'the irstparteof, the-pump as fuel is delivered as completion ofthe .pump vstroke the nozzle-50, keeps' up-`the accelerating chargeuntil the the piston is pressed l closely piston vwhenl near The normal fuel for rendering the' accel- The Voutlet from this reservoir has been emptied. -When the piston isvst'ationary, as when the throttle is held open, the high speed lnozzle tends -to dis 'charge all the fuel passing the orifice 37 so that the reservoir ordinaril until the acceleratingpumpis into action.

Figure 3 differs provision of a plain reservoir 51, checkevalve or auxiliary nozzle. Figure 4 resembles Figure 3,' with the provision of a weighted flexible diaphragm 52, for a top closure for the reservoir 51, instead of the closure shownin .Figure 3. '-Ihe flexible diaphragm expands upwardly as shown in dottedv lines to provide' thenecessary capacity during the initial stages of the pump stroke. p

Figure 5 illustrates a by-pass passa leading back-to the float chamber an 'controlled by an adjustable needle valve 54, to reduce the accelerating charge by providing a variable area by-pass -from the pump. The advantage ofsuch a structure will be evident again brought without a 1in permitting adjustmentof the' accelerating charge to suit individual engine requirements. l

Figures6 and 7 show 4two modifications of the auxiliary 'reservoir which are filled provided with an overiow tube 57, extending up to the normal liquid. level in the oat bowl Y to restrict the refilling to the movement of the pump while still having the independent refill passage 5.5. A vent 1tube 58, is provided to allowV the lescape of air from the reservoir to reduce the pressure required toginject a suitable amount of fuel thereinto. `-In this figure a plain no zzle 59,' is shown without provisionv for air admixture `With the fuel prior to the discharge thereof.

E In theoperation of these various modifica;4 i

tions the same objective is desired, namely, an

linitial injection of fuel-above a predetermined suddenness of operation of the pump followed by a sustained or auxiliary accelerwill not refill from Figure 1 only in thel 'i ating'fuel discharge after the pump completes its' stroke. The by-pass back to the float bowl, as shown in Figure 5, may be used with any of the modifications to provide in" 1 dividual adjustments of the total amount of the accelerahng charge I am aware made, and numerous details of construction `may be varied through a wide range without de from the rinciples of this inthat changes may bev las vention, and therefore o'not'purpose limit-Y l ing the patent granted hereon, otherwise th ,neeeitateli prior art.

I claim as my invention:V v

1. In combination with an accelerating pump and the dischargenozzle therefor, a passage connecting the pump to the nozzle,

lmeans associated with the pump for 'varying the effective area of said passage during the movement of said pump, and means for storing a part of the pump discharge adapted .to maintain the delivery of theaccelerating chargeA after the cessation of the pump stroke.

- sageway comprising a variableorice, means operable by said pumping means for Varying 2. Ina carburetor, a source of fuel supply,

a dischar e nozzle therefor, means for con` trolling t e flow of fuel, through said pasthe size ofsaid orifice when the pumping means is brought into play to discharge acof said pumping meansand during the time l said source of supply is again being connected to said passageway.

` 5. In a carburetor, a throttle operated accel` erating fuel pumping means, a main carburetor fuel discharge passageway connected thereto, a source of fuel supply or saidpas-` sageway, a discharge'nozzle for said pumping means, said main passageway being arranged to supplythe normal'n'eeds of the carburetor when said pumping means is idle, valve means associated with `said pumping means for shutting off said source of supply to said passageway during the discharge stroke of said vpumping means to cut off the normal dis-A charge from said passageway,land means con nected to said pumping means for storing fuel adapted to maintain the dischargeof accel# erating fuel through said nozzle after the cessation of the discharge stroke o f said pumping means, said storage means belng ar- 'ranged so as notto have the fuel withdrawn therefrom through said passageway wherebyl said pumping means can again be charged with fuel during the discharge of fuel from said storage means.- j

In testimony whereof I have scribed my name.

'CHARLES n. `:Knusic hereunto subcelerating fuel through said nozzle, and a` fuelstorage chamber connected to said pumping means so as torecelve fuel therefrom .o n

the discharge'stroke, of the pumping means and adapted tosupply. additional accelerating fuel to said'nozzle after the cessation of the L carburetor when vsaid pumping means discharge stroke of said pumping means.

4. In 'a carburetor, throttle controlled pumping means, 4a 'nozzle connected therewith, a main carburetor fuel passageway connect'ed to said pum ing means, a source of fuel supply adapte 'to be connected to said passageway, said main passageway being arranged to supply'- the normal needs of the idle, said pumping means having associated l therewith a storage .space for fuel' in communication 'with said nozzle and valve' means for automatically .shutting olf the source of fuel supply from said passageway upon the actuation of said pumping means to cut ofi` the' normal discharge of fuel therefrom vand whereby accelerating fuel is discharged from Y "being adapted to be opened by vthehreturn said nozzle by said pumping means independent of said source of supply, said valve means stroke of said pumping means-whereby the pumping means is charged with. fuel from said sourceas said source is again connected Vto said passageway, said storage space being connected with said pumpingmeans to have stilo.

' izo V' 

